From ead0cfe68e04c167034405a785878058ceb6d589 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 7 Jun 2020 12:19:06 -0700 Subject: [PATCH 2/2] vfs: clean up posix_acl_permission() logic aroudn MAY_NOT_BLOCK posix_acl_permission() does not care about MAY_NOT_BLOCK, and in fact the permission logic internally must not check that bit (it's only for upper layers to decide whether they can block to do IO to look up the acl information or not). But the way the code was written, it _looked_ like it cared, since the function explicitly did not mask that bit off. But it has exactly two callers: one for when that bit is set, which first clears the bit before calling posix_acl_permission(), and the other call site when that bit was clear. So stop the silly games "saving" the MAY_NOT_BLOCK bit that must not be used for the actual permission test, and that currently is pointlessly cleared by the callers when the function itself should just not care. Signed-off-by: Linus Torvalds --- fs/namei.c | 2 +- fs/posix_acl.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index e74a7849e9b5..72d4219c93ac 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -271,7 +271,7 @@ static int check_acl(struct inode *inode, int mask) /* no ->get_acl() calls in RCU mode... */ if (is_uncached_acl(acl)) return -ECHILD; - return posix_acl_permission(inode, acl, mask & ~MAY_NOT_BLOCK); + return posix_acl_permission(inode, acl, mask); } acl = get_acl(inode, ACL_TYPE_ACCESS); diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 249672bf54fe..95882b3f5f62 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -350,7 +350,7 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want) const struct posix_acl_entry *pa, *pe, *mask_obj; int found = 0; - want &= MAY_READ | MAY_WRITE | MAY_EXEC | MAY_NOT_BLOCK; + want &= MAY_READ | MAY_WRITE | MAY_EXEC; FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { -- 2.27.0.rc1.8.g04bd0c80d7